Carburetor



H. FORD CARBURETOR Nov; 11, 1930.l

Filed June 16, 1928 Patented Nov. 11, 1930 UNITED STATES PATENT OFFICE HENRY FORD, OF DEARBOBN, MICHIGAN, A'SSIGNOR TO FORD MOTOR COMPANY, OIE' DEARBORN, MICHIGAN, A CORPORATION OF DELAWARE CARBURETOR Application vfiled June 16,

The object of my invention is to provide a carburetor of simple, durable and inexpensive construction. Still a further object of my invention is to provide a carburetor made from two castings which are so shaped that they may be jointed v together at approximately the middle horizontal plane of the carburetor and secured together by a single bolt whereby the assembly and disassembly of the carburetor for repair or adjustment may be greatly simpliied.

Still a further object of my invention is to provide a carburetor having two fuelj'ets for normal running operation one of which has a practically unrestricted flow during the low vacuum eriod of carburetor use and a restricted iiow during high vacuum and the other has a restricted flow at all times whereby plenty of fuel will be supplied to the zo th oat of the carburetor when the engine is running at low speed but the flow of the fuel at high engine speed will not be increased out of proportion to the increased fuel requirement.

Still a further object of my invention is to provide in combination with such a carburetor a manually controlled fuel supply which may be linely metered to adapt the carburetor to various engines or various climatic or fuel conditions.

Still a further object of my invention is to provide in combination with such a carburetor, a compensating well whereby a reserve g supply of fuel always may be available when the engine is changed from an idling to an operating speed. l

Still a further object of my invention 1s to provide a. controlling device for a carburetor of the type specified wherein a single control rod may be used for operating both `the manually controlled fuel supply and for operating a choke valve.

Still a further object of my invention is to rovide such a carburetor control rod Where- 1n rotation thereof will adjust the needle valve and reciprocation thereof will operate the choke valve but either rotation or reciprocation thereof will not affect the possibility of simultaneously or independently adjusting the choke and needle valve. v

192s. serial No. 285,907.

Still a further object of my invention is to provide such a controlling device wherein the lparts may be very readily made on the production basis and their assembly or disassembly may be readily accomplished.

With these and other objects in view my invention consists in the arrangement, construction and combination of the various parts of my improved carburetor, as described in the specification, claimed in the claims, and illustrated in the accompanying drawings, in which:

Figure 1 shows a diagrammatic and schematic view of my improved carburetor showing the operation of the Various parts thereof.

Figure 2 shows a vertical longitudinal central sectional View through my improved carburetor.

Figure 3 shows a horizontal sectional view taken on the line 3-3 of Figure 2.

Figure 4 shows an elevation of my improved carburetor illustrating its manner of installation on an engine, and

Figure 5 shows a sectional view taken on theline 5-5 of Figure Il.

Referring to the accompanying drawings, I have used the reference numeral 10 to indicate generally the casting forming the upper portion of my carburetor and the reference numeral 11 to indicate generally the casting forming the lower portion of my carburetor. These two parts are secured to'- throurfh the lower casting 11 and is threaded into the upper casting 10.` The two castings have a liquid tight joint formed therebetween by means of the gasket 13. The bolt 12 is provided with a lock washer 14 which prevents it from unscrewing accidentally. At the right hand end of this casting 10, it is provided with an upwardly opening cup or chamber 15 which forms the bottom and sides of the float chamber for my improved carburetor.

A metallic iloat V16 is disposed in this chamber and supported on a yoke 17 which is pivoted at 18 to the yoke 19 which is suitably secured to the bottom of the upper casting 10. From the foregoing it ,will lbe seen that the bottom and sides of the float ether by a single bolt 12 which extends up but that the float is supported by the upper casting which is separable from the lower casting, so that the separation of these two castings does not necessitate any alteration or movement of the float mechanism but at the same time the construction makes said mechanism readily accessible for any inspection or adjustment.

The valve assembly is secured in a bore 20 in the upper casting 10 directly over the float 16 so that when the latter is in lits upper position, Vthe valve will be closed. This assembly consists of a sleeve 21 having a valve 22 mounted therein for vertical movement whereby the extending end of the valve 22 may be operated by movement of the float 16 to admit fuel to the float chamber to fill the latter to a predetermined level. The sleeve is secured in place in the casting in any suitable manner as by means of threads 23 so that the assembly may be removed for inspection or replacement.

A horizontal duct 24 is formed in the j Y 27, a cylindrical screen 28, and an end member 29, these parts vbeing arranged from right to left in the order named. A gasket 30 is mounted between the casting 10 and the head 25 to.secure a fuel tight joint between the parts.

The opening between the duct 24 and the bore 20 is somewhat restricted and the cylindrical screen 28 is of slightly less diameter than the major portiorrcf the duct 24 so that fuel which enters the duct 24 will flow through the screen 28 from the outside thereof to the inside thereof and then throughl the end29 into the bore 20. This end 29 is of such dimensions and is so placed that Fuel is supplied to the duct 24 by means of a fuel supply pipe 48 which is connected by a pack nut 49 with an elbow 50 which screws into an opening in the casting l0 which communicates with the duct 24.

The air entering my improved carburetor to be mixed with vaporized liquid fuel passes through the horizontal air inlet passage 31 and then turns and passes upwardly through a venturi; 32 into a vertical mixture passage 33l in the upper casting 10, from which it passes into-an engine intake man1- 'fold 34. The upper casting 10 is secured to thisv intake manifold by means of bolting flanges 35v which extend from lthe manifold 34 and casting 10, these parts being held together bythe cap screws 37 and a liquid tight joint being insured by the gasket 36. The air which is supplied to the air inlet passage 31v is drawn vthrough an air pipe 38 which may be connected to any suitable supply of air such forA instance as an air cleaner or a stove for heating the intake air by means of the exhaust manifold heat. The air inlet passage is provided with a choke valve 39 which is mounted on a shaft 40 which extends through the air inlet assage 31 so that the amount' of air a mitted through the air inlet passage to the venturi 32 may be restricted to thereby increase the suction on the fuel jets. A throttle valve 41 is mounted in the fuel passage33 and sup ported b a shaft 42 in said passage.

This shaft 42 extends outwardly through the wall of the casting 10 and carries an actuating arm 43 at the outer end thereof de` signed to be connected through a ball joint 44 with a carburetor control rod 45. An adjustable stop screw 46 is mounted on the castingl() in position to co-act with a lu 4'( extending from the arm 43 lwhereby ti ing movement of the throttle valve 41 may be limited to thereby insure the proper position of the throttle valve 41 when the engine is idling.

A Venturi structure of my improved carburetor is formed by slipping a sleeve into the mixture passage 33, this sleeve having a shoulder 52'near the lower end thereof which contacts with the lower surfacevof the e closgasket 13 to limit the movement of the sleeve 51 into the mixture passage 33. The lower end of the sleeve 51 below the shoulder 52 is slotted at the opposite sides thereof to receive the arms 54 which extend from the auxiliary demountable sleeve 55. These arms 56 also bear against an annular flange or shoulder 56 in the lower casting 11 whereby the clamping of the castings 10 and 11 together by means of t-he screw '12 may clamp the Venturi assembly comprising the sleeves 51 and 55 between the shoulders 56 and the gasket 13. This makes it possible to assemble and disassemble the Venturi struc! lll end is larger than the upper end due to the shoulder 52.

When metered jets are provided for atomizing the fuel in connection with carburation, it has been found that a metered jet which issized to give the correct mixture when there is a low vacuum in the carburetor vwill not give a proper mixture when there is a high vacuum in the mixing chamber as a jet which gives the proper fuel mixture for low vacuum will give too much fuel under high vacuum conditions.4 On the other hand, a jet metered for correct mixture under high vacuum will not give enough fuelfor low vacuum conditions. In my improved carburetor, I have therefore provided a single metered jet 57 which gives just a part of the fuel required for operating the engine at all speeds. This jet being of the ordinary metered type will ofv course increase its flow with varying vacuum conditions so as to give more fuel at higher engine speeds and relatively less fuel at lower engine speeds. This jet 57 is connected with the carburetor drain well 58 which is normally sealed by a cap screw 59 and a gasket 60. A passageway 61 is drilled between this drain well 58and the float chamber 15 to supply the fuel for the jet 57.

A compensating jet 62 also extends up to the sleeve 55. This jet 62 communicates through the passageway 63 with a compensating well 64 which is formed in the casting 11. This well is connected through a metered hole 65 with the float chamber 15. From the foregoing it-will be seen that fuel may flow quite freely from the well 64 through the passageway 63 and out of the jet 62 as these passageways are relatively large and the fuel may consequently be drawn therefrom by relatively low vacuum. As the speed of the engine is increased the fuel in the well 64 is drawn out by the vacuum in the jet 62 more rapidly than it may flow by gravity through the hole until the fuel level in the well 64'lowers even with the passageway 63, at which time the fuel supplied by the jet 62 is limited to the amount which may flow by gravity through the opening 65. In other words this compensating jet 62 furnishes a relatively large supply of fuel with relatively low vacuum conditions in the manifold for low engine speeds but limits the total amount of fuel which may be drawn therethrough at high engine speeds due to the metered hole 65.

From the foregoing it will be seen that the jets 57 and 62 automatically tend to proportion the fuel supplied thereby to the vacuum created by the action of the engine. That is, the jet 57 tends to feed more fuel in proportion as the engine speeds up thereby compensating for the additional fuel required while the jet 62 tends to feed more fuel in proportion while the engine is running slowly or accelerating from idling but the total amount for this jet is limited to a predetermined maximum by the metered opening 65 from the float chamber 15. A duct 66 is further provided which receives fuel supplied through a needle valve construction from the float chamber 15. This fuel is supplied to the jet 62 and supplements the fuel supplied to Said jet by the metered opening 65. i. y

The needle valve construction receives the fuel from the duct 67 which in turn communicates with the float chamber 15 and the valve 68 may be adjusted to control the additional fuel fed through the duct 66 into the jet 62. From the foregoing it will be seen that the needle valve 68 may be manually adjusted to supply additional fuel to the engine when same is desired on account of variations in temperature, atmospheric conditions, or engine requirements.

An idling jet 69 is mounted in the casting 10` and extends down into the well 64. This idling et 69 extends down into the pocket at the bottom of this well which is below the level of the duct 63 and the metered hole 65 so that there is always gas in the bottom of the well under all carburetor conditions as the duct 63 will not draw the gas out of the bottom of this well 64 far enough down to drain the well.

A manually adjustable air inlet 70 is formed in the casting 1() and designed to admit air to a mixing chamber 71 which surrounds the jet end of the idling jet 69. The amount of air admitted is adjusted by the relatively large needle valve 93. The mixed air and fuel from the Vchamber 71 passes through the priming hole 7 2 into the top of the fuel passage 33 at approximately the level with the throttle valve 41. It will thus be seen that the vacuum created in the manifold by the closing of the throttle valve 41 will suck up air and fuel from the chamber 71 into the manifold. This inlet of fuel provides for the supplying of the engine with the idling mixture. Of course the closing of the throttle cuts the vacuum in the fuel passage 33 of the air inlet 3l down to practically nothing so that substantially no fuel is taken from the jets 57 and 62 during the time that the throttle valve is closed to cause the engine to idle. It may be mentioned here in passing that the air inlet 70 for the idling mixture also ser'ves to admit air into the well 64 to mix with the fuel taken therefrom by the jet 62 at high speeds of the engine.

The needle valve 68 is mounted in a laterally extending portion of the casting 11. A relatively large well 74 is drilled down into the extension 7 3 and the top of this well is closed by a gland nut 75 which is screwed down into the top of the well by means of a pipe thread 76. The needle valve 68 passes through this gland nut 75 and is threaded at 77 to cause it to be vertically adjustable in this gland nut so that the point of vthe valve` 68 may be adjusted to meter or shut off the fuel supplied through the duct 66. A sleeve 78 is for-med integral with the gland nut 7 5 and extends upwardly therefrom. The valve 68 also has an extension 69 which extends up through this sleeve 78 but this extension instead of being round like the balance of the valve 68 is half ground as clearly appears in Figure 5.

An intermediate connecting assembly is formed to connect the combined choke and carburetor adjusting rod 80 with the needle valve 68 and the choke valve operating shaft 40. This assembly comprises a rod 81 whlch has its lower end half round and of such di-l ameter that it may slidingly extend into the sleeve 78 and co-act with the half round end 79 of the needle valve 68 to lill the interior of the sleeve 7 8 whereby rotation of this rod. 81 will rotate the needle valve 68 but the reciprocation of this rod 81 within the sleeve 78 may be permitted without affecting the rotary driving connection between the rod 81 and the valve 68'. A. sleeve member 82 is pinned as at 83 to the rod 81 and extends down over the sleeve 78 to have a. telescopic connection therewith. In other words the sleeve 82 can rotate relative to the sleeve 78 and slide thereon.

A pair of flanges are formed at the lower end of the sleeve 82 so that a channel 84 is formed between these flanges which is designed to receive the inwardly extending pin 85 on the free end of the arm 86 which is fixed to the choke valve operating shaft 40 by the nut 87.

From the foregoing description it will be seen that rotation of the rod 81 rotates the valve 68 to adjust same while reciprocation of the rod 81 will swing the arm 86 to operate the choke valve 39. The driving connection between the rod 81 and the valve 68 remains the same however, in any of the positions of the rod 81. In other words rotation and/or reciprocation of the rod 81 will rotate the valve 68 and/or operate the choke valve 39. The adjacent ends of the connecting rod 81 and the operating rod 80 are formed with complementary shapes whereby when these complementary shapes are moved into engagement so that longitudinal and rotary movement of the rods relative to each other is prevented but they may be moved laterally out of engagement with each other. These interfitting shapes are llat surfaces having generally the outline of a block type S as is indieated by the lines 88 in Figure 5. Y

As is usual in connection with such operating rods, this rod 80 passes through a dash member 89 and a sleeve 90 is slidably mounted on the rods 81 and 80 adjacent to the sleeve 82 and is of such dimensions that when these two parts interlock at their adjacent ends, then that sliding the sleeve 90 down over the interlocked portions will prevent movement of these rods relative to each other as the interlocking portions prevent rotary or longitudinal movement and the sleeve prevents lateral movement of the rods relative to each other.

The sleeve 90 is yieldingly urged into lts position which holds the rods interlocked with each other by a spring 91 which extends between the dash 89 and the flange 92 on the sleeve 90. This spring 91 has the double function of holding the sleeve 90 in place so that the rods 81 and 80 will be locked together and also of tending to press the operating rod 80 to its lower position whereby it yieldingly urges the choke valve 39 to its open position.

From the foregoing it will readily be seen that the joint between the rods 80 and 81 is such that these two parts may be readily connected'and disconnected if the carburetor is to be removed as these rods may be disconnected by simply pulling up the sleeve 90 against the pressure of the spring 91 which permits the rods 80 and 81 to move apart laterally from each other. When these parts are again connected, the spring 91 has the further function of holding the choke valve open unless the rod 80 is held in position to -move the choke rod to some other position.

Among the many advantages derived from the use of my improved carburetor, it should first be pointed out that I have provided means to cause the carburetor to automatically compensate for varying vacuum conditions in the mixing chamber due to varying engines speeds and at the same time I have provided a manual metering control for supplying additional fuel to make the carburetor manually adjustable for climatic, temperature, or engine conditions.

Still a further advantage results from the two part casting construction used in connection with my carburetorl which seals in the liquid fuel against leakage much more easily and at the same time permits ready separation of the carburetor parts for repair or adjustment and to permit draining of the carburetor. Still a further advantage results from the use of my improved carburetor with the control rod which both adjusts the needle valve and closes the choke valve.

In this improved mounting, the sleeve 90 and spring 91 have the double function of permitting ready removal of the parts for repair or adjustment and of normally holding the choke valve in its open position. Still a further advantage of this choke valve mounting construction is that the parts are readily manufactured on a production basis but are extremely durable, strong and not at all liable to get out of order.

Some changes maybe made in the arrangement, construction, and combination of the various parts of my improved device without departing from the spirit of my invention, and it ismy intention to cover by my claims, such changes as lmay reasonably be included within the scope thereof.

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l opening connectingthe float chamber and compensating well, an unrestricted opening connecting the compensating well and the mixture passage, and-a metered opening connecting the unrestricted opening and the float chamber.

2. In a device of the character described, a carburetor having a ioat chamber and a compensating well and a Venturi chamber, a fixed metered opening connecting the float and Venturi chambers, a fixed metered opening connecting thel compensating Well and the oat chamber, an unrestricted opening connecting the compensating well and the Venturi chamber, and a manuallv adjustable metered opening connecting the unrestricted opening and the oat chamber.

3. In a device of the character described. a carburetor having a float chamber and a compensnting well and a Venturi chamber. anv

opening having a fixed metered iet therein connecting the iioat and Venturi chambers. a second opening having a fixed metered iet therein connecting the float chamber and compensating well. an unrestricted opening connecting the compensating well and Venturi chamber. and a manually adiustable metered opening connecting the unrestricted opening and the oat chamber.

' 4. -In a device of the character described. a carburetor having a Heat chamber and a compensating well and a Venturi chamber and `a mixture passage. a fixed metered opening connecting the oat and Venturi chambers, a fixed metered opening connecting the compensating well and the float chamber. an unrestricted opening spaced from the bottom of the compensating well connecting the Venturi chamber and 'the compensating well. a manuallv adiustable metered opening connecting theunrestricted opening with the float chamber. a manuallv adinstable air inlet opening connected with themixture passage bevond the Venturi chamber. and a fixed metered opening connecting the bottom of the compensating well with said air inlet for supplying fuel to said adjustable air inlet.

5. In a device of the character described, a carburetor having a Venturi chamber, a

' metered jet connecting said Venturi chamber with the carburetor float chamber, a relatively unrestricted jet connecting said Venturi chamber with a compensating Well, a metered opening connecting said compensat` ing well with the carburetor ioat chamber, anda manually controlled valve designed to supply additional quantities of fuel to the compensating well independently of said metered opening to compensate for climatic and temperature changes.

6. In a device of the character described, a carburetor having a float chamber and a compensating Well and a mixture passage, a metered opening connecting the float chamber and mixture passage, a relatively fixed opening connectin the float chamber and the compensating wel an unrestricted opening connecting the compensating Well and the mixture passage, and manually controlled means for supplying additional quantities of fuel to the compensating well to oompensate for climaticV and temperature changes.

June `4:, 1928.

HENRY FORD. 

